CTET CTET Math 5 — Questions and Answers
Question 1: Which of the following is an irrational number?
- √49
- √36
- √50 (Correct answer)
- √81
Correct answer: √50
√50 = 5√2, which cannot be expressed as p/q, so it is irrational.
Question 2: The speed of a boat in still water is 12 km/h and the speed of the stream is 4 km/h. Time taken to go 48 km downstream is:
- 6 h
- 4 h
- 3 h (Correct answer)
- 5 h
Correct answer: 3 h
Downstream speed = 12 + 4 = 16 km/h; time = 48/16 = 3 hours.
Question 3: In a bar graph, if the scale is 1 cm = 50 units and a bar is 3.5 cm tall, what value does it represent?
- 150
- 175 (Correct answer)
- 200
- 125
Correct answer: 175
Value = 3.5 × 50 = 175 units.
Question 4: The LCM of two numbers is 120 and their HCF is 10. If one number is 40, the other number is:
- 30 (Correct answer)
- 60
- 20
- 50
Correct answer: 30
Product of numbers = LCM × HCF = 1200; other number = 1200/40 = 30.
Question 5: A student says '2 + 3 × 4 = 20'. This reflects a misconception about:
- Place value
- Order of operations (BODMAS) (Correct answer)
- Commutativity
- Associativity
Correct answer: Order of operations (BODMAS)
The student added before multiplying, violating BODMAS where multiplication precedes addition.
Question 6: The angle subtended by a semicircle at the centre is:
- 90°
- 270°
- 180° (Correct answer)
- 360°
Correct answer: 180°
A semicircle subtends an angle of 180° at the centre since it is half the circle.
Question 7: Which of the following best describes a 'mathematical error' as an assessment tool in CTET pedagogy?
- Proof of student carelessness
- A window into student thinking and misconceptions (Correct answer)
- Reason to reduce marks only
- Evidence of poor teaching
Correct answer: A window into student thinking and misconceptions
CTET pedagogy treats errors as diagnostic tools revealing the learner's conceptual gaps.
CTET CTET Math 5
Which of the following is an irrational number?